The present application relates to a photoactive compound including an oxime ester group and a phosphonate group, and a photosensitive resin composition comprising the same.
Photosensitive resin compositions may be used in forming a pattern by being applied on a substrate to form a coated film, and, after exposure by light irradiation is performed on a certain part of this coated film using a photomask and the like, the non-exposed area being removed using development. These photosensitive resin compositions are used in photocurable inks, photosensitive printing plates, various photoresists, color filter photoresists for an LCD, photoresists for a resin black matrix, or transparent photosensitive material, since it is possible to polymerize and cure these photosensitive resin compositions by light irradiation.
Among these, transparent photosensitive resin compositions are used for column spacers, overcoats and passivation films, typically do not use coloring compounding such as pigments, and include an alkali-soluble resin, a polymerizable compound having an ethylenic unsaturated bond, a photopolymerization initiator, and a solvent.
Among these, coloring photosensitive resin compositions are used for color filter photoresists and photoresists for a resin black matrix, and typically include a red, green, blue or black coloring agent, an alkali-soluble resin, a polymerizable compound having an ethylenic unsaturated bond, a photopolymerization initiator, and a solvent.
With the application of an LCD being high-quality and diversified, photosensitive resin compositions are manufactured to be used in composing the liquid crystal display devices of televisions and monitors, in addition to conventional uses such as for notebook computers and mobile devices, and demand for compositions that react to light quickly and have excellent mechanical properties has increased in order to improve productivity and resistance. The characteristic of reacting to light quickly, that is, photosensitivity, is becoming a factor that plays a very important role when a pattern is formed using a photolithography method, or when an insulator protective film is formed through whole exposure. In addition, a column spacer, which plays the role of a support, or an overcoat and a passivation film, which play the role of a protective film, must have excellent mechanical properties, so that a liquid crystal display device is not damaged by shocks applied from the outside, but retains its original performance.
Consequently, these problems can be solved using a photopolymerization initiator having excellent photosensitivity. When a photopolymerization initiator having excellent photosensitivity is used, sufficient sensitivity can be achieved even with small amounts of the photopolymerization initiator, and thus there are advantages in that the breadth of availability of other raw materials increases when a composition is prepared, the causes of pollution attributable to a liquid crystal are reduced, and the retention rate of a pattern increases.
Therefore, there is the demand for the development of a photopolymerization initiator that efficiently absorbs UV light source even when it is used in small quantities, and has excellent sensitivity and high-temperature process properties.